In the related art, there is known, for example, a touch panel system disclosed in PTL 1 as a touch panel system that detects the position of the touch of a touch pen on a touch panel which has electrostatic capacitances formed at each intersection of a plurality of first signal lines and a plurality of second signal lines.
The touch panel system disclosed in PTL 1 includes a plurality of electronic pens, a panel main body that includes a touch face on which a touch operation is performed by the electronic pens and a finger and in which a plurality of transmission electrodes that runs parallel to each other and a plurality of reception electrodes that runs parallel to each other are arranged into a lattice, a transmission unit that applies a drive signal to the transmission electrodes, a reception unit that receives a response signal which is output from the reception electrodes in response to the drive signal applied to the transmission electrodes and outputs detection data for each intersection of the electrodes, and a control unit that detects the position of a touch on the basis of the detection data which is output from the reception unit, in which the transmission unit applies a pen synchronization signal that synchronizes the transmission and reception of a pen identifiable signal between the electronic pens and the reception unit to the transmission electrodes, the electronic pens transmit the pen identifiable signal to the reception electrodes in response to the detection of the pen synchronization signal in the transmission electrodes at the time of a touch operation, and the control unit, on the basis of the pen synchronization signal that the reception unit receives through the reception electrodes, identifies a pointed object on which a touch operation is performed.
According to this configuration, a plurality of electronic pens can be used because each electronic pen transmits the pen identifiable signal to the reception electrodes in response to the detection of the pen synchronization signal from the transmission electrodes at the time of a touch operation and because the control unit, on the basis of the pen synchronization signal that the reception unit receives through the reception electrodes, identifies the electronic pen that performs the touch operation.
When an electronic pen that is provided with additional functions such as a pen pressure sensing function is used as the touch pen, it is necessary to transmit information that the electronic pen obtains to the touch panel controller.
In this case, for example, in the position detecting device disclosed in PTL 2, the electronic pen transmits information to the touch panel controller by using a signal that is configured of a plurality of types of codes which have different code patterns.